Re: [Emacs-diffs] master 19e09cf: Ensure redisplay after evaluation

[Stefan Monnier <monnier@iro.umontreal.ca>]

> AFAICT, these objections were never addressed in the discussions.

That's just a disagreement.  I don't think that can be addressed.
I fully agree with Richard that it's a facility with which you can shoot
yourself in the foot in many different ways, but I don't find it to be
a reason to disallow it.

After all, this same objection can be raised against lots of other "hooks"
we have.  To me it just means that it's a feature that needs to be used
with care, not that it's a feature we should reject.

> And we _are_ talking about using such a facility for purposes other
> than debugging, albeit internal purposes.

That's exactly why I think this feature should be generic (and hence
dangerous): there are several different potential valid applications,
and the reason why it's safe/acceptable can completely vary from one use
to another (e.g. in the debugging case you'll probably want to allow
the hook to make random changes, whereas in general this would be
completely unacceptable.  In the present case, the hook would be
perfectly acceptable because its effect is "unnoticeable" since all it
does is set a flag somewhere).


        Stefan